Most modern buildings require a ventilator system to provide a supply of fresh air into the building interior. In addition, most ventilation systems act to regulate the internal temperature of the building where occupants, equipment and solar heat increase the building's internal temperature which if unregulated becomes uncomfortable and can be harmful to electronics equipment for example.
Most territories have regulations that establish minimum fresh air requirements for the building interior depending upon intended usage and occupancy levels. Typically, most commercial buildings utilise electricity driven air conditioning systems that both circulate air within the building and provide internal air temperature control.
In response to climate change and in particular global warming, international legislation has imposed emission limitations and energy efficiency requirements. Accordingly, certain territories have introduced regulations on the energy performance of buildings which in some counties manifests as an annual carbon emission rating. This increased awareness of the carbon footprint of buildings, has led to the re-examination of the energy performance and suitability of all systems associated with the building that consume energy. Various ventilation devices have been proposed to increase the thermal efficiency of building ventilation. In particular, WO 2006/006827 discloses a heat recovery ventilation device which transfers heat between air exhausted from a room (during ventilation) and fresh inlet air to provide a supply of a heated fresh air. Other ventilators and ventilation systems directed to improving the thermal efficiency of a building are described in KR 10-0974085; DE 10 2005016913; DE 10 2006001724; JP 2005-282927; JP 2006-132884. However there exists a need for a building ventilator that improves the efficiency by which energy may be transferred during the ventilation and supply of fresh air at a building interior.